On Sunday, avalanche warnings were posted in parts of California, Nevada and Utah because of the heavy snow the storm dumped on the region.

The Sierra Avalanche Center issued a backcountry avalanche warning for the Lake Tahoe area stretching south into the Sierra along the California-Nevada line from noon Sunday until 7 a.m. Monday.

The National Weather Service says blizzard conditions with gale-force winds could trigger widespread avalanche activity.

Cleanup work kept about 13 miles of the scenic Pacific Coast Highway closed from western Malibu to Ventura County. Caltrans said the closure might last into Tuesday.

Photos from the scene showed several vehicles swamped by mud and debris in the area.

A National Weather Service report said the mud and debris flow was about the size of two football fields.

"I'm just thankful to be alive. I don’t care about the car," said Rapper Soulja Boy, who was among the motorists whose cars were trapped by the mudslide. "It’s materialistic. You can’t take it with you when you’re gone."

No injuries were reported after heavy rains swept through greater Los Angeles, loosening hillsides in areas scorched by recent wildfires.

The same weather system has also brought strong winds to the Pacific Northwest, knocking out power and downing trees in parts of Washington and Oregon.

At one point Sunday morning, more than 290,000 customers were without power in western Washington and Oregon, according to PowerOutage.us. Sea-Tac airport in Seattle reported a wind gust to 60 mph at 2 a.m. Sunday.

The power outage apparently caused Alaska Airlines to order a nationwide ground stop. The airline says all its flights were grounded between about 4:20 a.m. and 5:15 a.m. Sunday after an outage in the Seattle area, where its operations are based.

Airline spokeswoman Oriana Branon says the power went out around 3:30 a.m. and came back on about an hour and a half later. She says 27 flights were delayed and five were canceled.

Dozens of flights into and out of San Francisco International Airport were canceled and hundreds delayed because of the weather on Saturday and Sunday.

In northwest Oregon, thousands of Portland General Electric customers lost power from a burst of high winds Saturday night. A wind gust to 54 mph was clocked at Portland International Airport.

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